An organic thin film photovoltaic cell is a photovoltaic cell prepared by using an organic thin film semiconductor in which a conductive polymer, fullerene and the like are combined. In the organic thin film photovoltaic cell, a photoelectric conversion film can be produced by a simple method such as coating or printing and a lower cost may be achieved, compared with a photovoltaic cell based on an inorganic material such as silicon, Cu—In—Ga—Se (CIGS) or CdTe. In contrast, there is such a problem that the photoelectric conversion efficiency and life of the organic thin film photovoltaic cell are low in comparison with inorganic photovoltaic cells in the related art.
One of factors responsible for the decreased photoelectric conversion efficiency of an organic thin film photovoltaic cell module is such a factor that the efficient extraction of photocurrent to the outside requires reduction in photovoltaic cell area to around 10 to 20 mm since a transparent electrode has relatively high resistivity. When photovoltaic cells composing the photovoltaic cell module are small as described above, the total area of spaces in which the photovoltaic cells are electrically connected is increased to decrease an opening ratio in the photovoltaic cell module.
The problem occurs not only in organic thin film photovoltaic cells but also in inorganic photovoltaic cells in which a transparent electrode of amorphous silicon, CIGS, or the like is used. In the inorganic photovoltaic cells, various devices have been accomplished for improving the opening ratio of a photovoltaic cell module. For example, a wiring pathway for connection between photovoltaic cells has been formed by a laser or mechanical scribing method in order to reduce connection spaces between the photovoltaic cells. However, laser and mechanical scribing systems have not yet been effectual measures in organic thin film photovoltaic cells. The systems are systems by which a part of a formed photoelectric conversion layer is thermally or mechanically removed and connection wiring is passed therein; however, in the laser scribing, since the efficiency of converting laser light into heat in an organic semiconductor layer is low, the organic semiconductor layer cannot be satisfactorily removed. In the mechanical scribing, it is also difficult to scrape off an organic semiconductor layer with a sharp share point, so that a fine connection wiring pathway cannot be formed, since the elasticity of the organic semiconductor layer is higher than that of an inorganic material. It is also a phenomenon peculiar to an organic semiconductor layer that string-shaped cutting scraps are easily generated and cannot be completely removed.